Contents of /trunk/escript/src/DataTagged.cpp

Added explicit destructors to all Exception classes.
Fixed an ifdef in TestCase.cpp
Made the conditional definition of M_PI in LocalOps.h
depend only on M_PI being undefined.
Replace dynamically dimensioned arrays in DataFactory & DataTagged with malloc.
sort() method of list does not take a named argument
(despite the manual's claims to the contary).